Gabions are temporary or semi-permanent fortification structures which are used to protect military or civilian installations from weapons assault or from elemental forces, such as flood waters, lava flows, avalanches, slope erosion, soil instability and the like. WO-A-90/12160 discloses wire mesh cage structures useful as gabions. The cage structure is made up of pivotally interconnected open mesh work frames which are connected together under factory conditions so that the cage can fold concertina-wise to take a flattened form for transportation to site, where it can be erected to take an open multi-compartmental form for filling with a suitable fill material, such as sand, soil, earth or rocks.
WO-A-00/40810 also concerns a multi-compartmental gabion which folds concertina-wise for transportation, and which comprises side walls extending along the length of the multi-compartmental gabion, the side walls being connected at spaced intervals along the length of the gabion by partition walls which are formed from two releasably connected sections, which after use of the gabion can be released, and the gabion unzipped for recovery purposes.
Existing gabions have certain disadvantages with respect to construction and longevity. For example, such gabions frequently comprise a wire mesh cage structure lined with a geotextile material, the lining adding to the cost and complexity of the gabion structure, and constituting a significant limitation on the functionality of the gabion after deployment over a long period of time. Particularly in harsh environmental conditions (intense sunlight, wind, rain, snow, sand or salt spray, or a combination of any two or more of these), the geotextile material tends to degrade and this can weaken the functionality of the gabion by, for example, the occurrence of rips, tears or holes in the liner, through which the gabion fill material can fall.